Enhanced electrochemical performance for sensing Pb(II) based on graphene oxide incorporated mesoporous MnFe2O4 nanocomposites

In order to seek for high performance electrochemical sensing materials toward heavy metal ions with excellent electrical conductivity, high adsorption capacity and good electrocatalytic activity, in this study, graphene oxide was incorporated with mesoporous MnFe2O4 (MnFe2O4/GO) to fabricate an electrochemical platform for sensing Pb(II). The as-prepared mesoporous MnFe2O4/GO nanocomposites contained uniformly MnFe2O4 particles with the diameter about 400 nm. The maximal pore diameter of MnFe2O4/GO was 4.5 nm and its specific surface area was obviously increased from 167.0 m2 g−1 to 285.7 m2 g−1 with the incorporation of GO. The CV, EIS and SWASV response toward Pb(II) showed the incorporation of GO would enhance the electrochemical activity of MnFe2O4 due to the improvement of specific surface area, electrocatalytic activity and conductivity supported by GO sheets. It provided the sensitivity of 33.9 μA/μM and LOD of 0.0883 μM for electrochemical detection toward Pb(II), and it was even suitable for the selective detection of Pb(II) in the presence of Zn(II). This MnFe2O4/GO modified electrode also presented satisfying reproducibility, stability, repeatability and applicability for detection of Pb(II). In short, it provides a simple and promising platform to develop novel electrochemical sensor for detecting heavy metal ions with high performance.